Man, I wish I could get back my 1 hour and 40 minutes. I really wanted to like this movie, but it was a disappointing mess with bad writing choices and piss poor dialogues. While the film's intentions may have been noble, National Anthem ultimately fails to deliver a compelling or memorable story. The characters are so flat, they might as well be cardboard cutouts.
Totally, a missed opportunity I guess the director didn't have a clue to flesh out the story from the POV of Dylan (Charlie Plummer), who does his best in parts and completely out of place and probably not going to end well. Of course he is a good actor, but even his talent can't overcome the sheer awfulness of the script. The only redeeming quality is the chemistry between him and his brother. Those scenes are standout, with good staging, backed with decent score in an otherwise boring film.
In conclusion, "National Anthem" ahh wish i can say it's decent but I'll value your time well, it's just bad. I recommend skipping this one.